Rune Blade

A Rune Blade (ルーンブレード, Rune Blade^?) is a Long Sword-class weapon Artifact introduced in Golden Sun: The Lost Age and featured in Golden Sun: Dark Dawn.

In Golden Sun: The Lost Age

Rune Blade (TLA)
Visual effect of Void Beam
In-Game Description
"Long Sword: Unleashes Void Beam" (TLA)
Trade Info
Weapon class	Long Sword
Buy value	15000
Sell value	11250
Artifact?	Yes
Statistic Boosts
Attack Boost	162
Unleash effect
Effect name	Void Beam
Extra damage	57
Side effect	May seal the target's Psynergy
Acquisition
• Random drop from Lesser Demon (TLA)

In The Lost Age, the first dungeon that can be accessed after the Reunion, Magma Rock, features the Lesser Demon enemy, which can drop a Rune Blade at a rare 1/128 chance. If it is slain by the attack of an offensive Jupiter Djinni, the chance quadruples to 1/32. Its Unleash effect, Void Beam (ボイドエナジー, Void Energy^?), adds 57 points of damage, aligns the damage to Jupiter overall, and causes a 55% chance to apply a Psynergy Seal that temporarily locks the target out from casting abilities that cost PP. Visually, Void Beam takes the form of the camera swiveling toward the backside of the enemy while a glowing image of a purple symbol "draws itself" line-by-line in front of the casting Adept. As soon as it is completed, the symbol instantly emits a thick, laser-like beam of whitish-purple energy that spans the screen, piercing through the target.

This weapon is almost identical to the Mythril Blade, a fairly common product of bringing a lategame-exclusive Mythril Silver to the Blacksmith in Yallam, the only appreciable difference being that its own Psynergy-sealing Unleash is aligned with Mercury instead. Because Void Beam is Jupiter-aligned, none of the four warrior-style Adepts can naturally capitalize on it with the higher elemental power ratings of their default mono-elemental class series: the Venus Adepts Isaac and Felix, the Mars Adept Garet, and the Mercury Adept Piers. It would take giving the Venus and Mars Adepts Jupiter Djinn to put them in the Apprentice and Page class series to improve the damage.

If you can get a Rune Blade to drop, it would make for a strong stopgap on the way to endgame-tier weapons like Sol Blade and Masamune, and more rarely Excalibur and Tisiphone Edge, all of which have damage-multiplying Unleashes. If you do not go out of your way to get the latter two weapons, a Rune Blade will likely be kept by one of your warrior Adepts as a weapon that is mostly sufficient for the endgame, though a Stellar Axe – one of the more common outcomes of forging an Orihalcon – is a Jupiter-aligned weapon that is even stronger and can Stun enemies with its Unleash. If the Phaeton's Blade Light Blade is still on one of your warrior Adepts, getting a Rune Blade will be a fairly solid upgrade and will allow Phaeton's Blade to be passed onto either Ivan or Jenna.

Since the Rune Blade is a rare drop, the Random Number Generator can be abused to guarantee it will drop:

RNG manipulation method

Make sure no one is wearing cursed equipment, and save inside Magma Rock in an area that is capable of generating Lesser Demons as opponents. Hard-reset the game, reload the save, and enter one battle; if a Lesser Demon has not appeared, hard-reset and reload the save again. Once you get a random battle with at least one Lesser Demon in it as your first battle in that play session, have Felix, Sheba, and Piers respectively cast Clay Spire, Ray, and Frost, all with the arrow centered on the Lesser Demon you're trying to get the drop from, and have Jenna cast Aura. The enemies will not attack because it is the first turn of the current play session and no screen transitions have occurred in the field yet. Then, in the second turn, have Sheba defeat the Lesser Demon with an unleashed Jupiter Djinni like Whorl, moving fast enough that none of the other party members have moved yet.

In Golden Sun: Dark Dawn

Rune Blade (DD)
The DS model of the Rune Blade
In-Game Description
"Weapon: Long Sword" (DD)
Trade Info
Weapon class	Long Sword
Buy value	15000
Sell value	11250
Artifact?	Yes
Statistic Boosts
Attack Boost	162
First Unleash effect
Effect name	Life Nourish
Extra damage	25
Side effect	May heal the user by the amount of damage dealt
Second Unleash effect
Effect name	Vorpal Slash
Extra damage	16
Side effect	Hits each adjacent foe
Third Unleash effect
Effect name	Void Beam
Extra damage	57
Side effect	May Seal the target's Psynergy
Acquisition
• Reforge Rusty Sword found in the shallow spot south of Yamata City in the Eastern Sea (DD)

In Dark Dawn, the Rune Blade can be discovered in the form of a Rusty Sword hidden in a shallow patch of water south of Yamata City, meaning it can be reached as soon as the player begins the last third of the game set across the Eastern Sea. At any time, the player can visit Champa and unlock the Blacksmith service for Dark Dawn, which does not cost any coins to use. Therefore, leaving the Rusty Sword with the backsmith will freely convert it into the fully functional form of the Rune Blade, which you can pick up the next time you return to Champa from the overworld. The 162 Attack offered by the Rune Blade makes it a very strong weapon to start off the Eastern Sea segment with, and it will likely last just about the rest of the game.

The newly randomized Unleash system of Dark Dawn causes the Rune Blade to randomly choose between Void Beam and two other Unleashes that are available earlier through gathering "Unleash Experience" by striking with the sword. The first, Life Nourish (ライフナリッシュ, Life Nourish^?), is a Venus-aligned Unleash adding 25 flat damage and causing a 65% chance to heal the user by the amount of damage dealt. The second, Vorpal Slash (ウインドウィーゼル, Wind Weasel^?), is a Jupiter-aligned Unleash that adds 16 damage and additionally strikes each adjacent enemy for 80% of the attack's overall force. Void Beam, which remains the Rune Blade's exclusive and signature Unleash, is unlocked last, and mastering the Rune Blade makes its probability of being chosen a little higher than the other two (and also adds bonus Attack points to the weapon as a whole).

Neither Matthew nor Tyrell, the only two party members who can equip Long Swords, feature mono-elemental class series that align with the Rune Blade's two Jupiter Unleashes (though Matthew's Venus class series at least improves Life Nourish). Much like in the previous game, assigning Jupiter Djinn to them to make them Enchanters or above will add Jupiter power (and also bring Tyrell's Attack rating in line with Matthew's). Only the game's very best weapons can reliably replace the Rune Blade, such as the Sol Blade at the final dungeon for Matthew and the Levatine or Masamune for Tyrell.

Gallery of Dark Dawn unleashes

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  Life Nourish

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  Vorpal Slash

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  Void Beam